A:AnswerFor which port? The wattage could be as low as 50mW or as high as 5W. Depends on the port, the device connected to it, and whether or not that port is powered or not powered.
A:AnswerYes. USB-C is the Thunderbolt standard. Same as what Apple monitors use. I believe they will take HDMI as well. Apple monitors aren't Mac specific. You can use them with PC hardware.
A:AnswerYes, it works with my iPad Pro and the cable is long enough such that the hub sits flat on the table surface and doesn't dangle in midair as some other dongles do.